The Internet is populated with a large number of web sites that may be accessed by individuals (herein “users”) that browse the Internet. A “web site” may include one or more related web pages which may be delivered to the user's computer (or other device) for viewing by the user. Many web sites have a “main” or “home” web page that is typically the first page that is displayed to a user when the user accesses the web site. The user may then directly or indirectly request, receive and display the remaining (secondary) web pages associated with the web site from the main web page.
As shown in FIG. 1, a user 10 may access the Internet 30 using, for example, a computer 20 that is connected to the Internet 30 via a modem, local area network, wireless, satellite or other connection 40. Typically, the user 10 accesses the Internet 30 by activating a web browser software program 25 that is resident on the computer 20 such as, for example, Microsoft's Internet Explorer™ or Netscape Navigator™. The web browser program 25 sends a request over the modem or local area network connection 40 to a server 50 that is connected to the Internet 30. Typically, the user's computer 20 is set to initially contact the same server 50 each time the web browser 25 is opened to access the Internet 30. In response to the request from the web browser 25, the contacted server 50 may deliver a web page 60 to the user's computer 20 via the modem or local area network connection 40, which is then displayed on a monitor 28 of the computer 20. From this initially delivered web page 60, the user 10 may navigate to any of a host of other web pages by, for example, typing in the address associated with a desired web page or by activating a “hyperlink” (discussed below) that automatically delivers a web page associated with the hyperlink to the user's computer 20. The owners/operators of servers that deliver web pages over the Internet are referred to herein as “content providers.”
Many content providers attempt to include an array of interesting subject matter on their main web pages in an effort to attract substantial traffic to their web sites. These content providers also typically allocate space on their main web page and/or on secondary web pages for Internet advertisements. Herein, the term “Internet advertisement” is used to refer to any content that is included on an Internet web page or otherwise displayed on monitors (or other displays) of users viewing an Internet web page in return for some sort of compensation. Thus, the term “Internet advertisement” encompasses, for example, traditional Internet advertisements such as banner and pop-up advertisements, as well as less traditional forms of advertising such as paying to have information regarding your business placed in a favorable location in the listing of results for a search conducted by an Internet search engine. The compensation may comprise monetary payment(s) or may be something else of value such as payment in the form of goods, services, hosting reciprocal advertisements, etc. Internet advertising is growing in importance as an advertising medium for many businesses. As such, Internet advertising has become an increasingly lucrative source of revenues for many Internet companies such as Internet portals and search engine companies.
Internet advertisements come in a variety of forms, and may include text, icons, graphics, pictures, video clips, etc., some or all of which may promote products or services associated with the entity sponsoring the advertisement. In some instances, the Internet advertisement may simply be information that is displayed on a portion of a web-page (which is often referred to as a “banner” advertisement). Another common form of Internet advertisement is a “pop-up” advertisement, which refers to an advertisement that overlays a portion of a web-page (and which often is configured to “pop-up” over the web page content while the user 10 is viewing the web page 60. In many cases, an Internet advertisement can be “activated” in the sense that a user may select the advertisement such that another web page or other information is delivered to the user's computer. Most typically, an Internet advertisement is activated by activating a “hyperlink” that is embedded in the Internet advertisement. A hyperlink refers to a word, phrase, icon, picture or other object or region on the user's display that the user 10 (i.e., the viewer of the web page) can activate to link directly to a different web page that is associated with the hyperlink. When the hyperlink is activated, a request is sent to a server that hosts the web page associated with the hyperlink (the “target web page”) and, in response to this request, the server delivers the target web page to the user's computer where it is displayed to the user (either replacing the currently viewed web page or displaying the target web page in a separate window). In the Internet advertising context, the target web page will typically provide additional details regarding the entity, product or service that is the subject of the advertisement and/or may provide the user a mechanism by which the user can purchase the product or service over the Internet.
One common method that content providers may use to charge for “hosting” or “posting” Internet advertisements on their respective web pages is to bill the businesses whose advertisements are displayed based on the number of times that viewers activate hyperlinks that are embedded in the posted advertisements. The most common method for a user 10 to activate a hyperlink is to move a pointing device such as a computer mouse so that the cursor is positioned over top of the hyperlink, and to then click on a button on the mouse with the cursor in that position to activate the hyperlink. Accordingly, the above-described method of paying for Internet advertisements based on the number of times users “click” on the advertisement is often referred to as a “pay-per-click” method. The pay-per-click payment method is, in effect, a way that an entity sponsoring an Internet advertisement can pay the content provider that posts the advertisement for each actual referral. This manner of payment has grown in popularity as it allows the payment for the Internet advertisement to reflect how effective the advertisement was in directing viewers (users) to seek out additional information regarding the advertised product or service. In many instances, companies may pay the content providers that post Internet advertisements a substantial sum per click (e.g., $0.50 or more per click), which may generate substantial advertising revenues.
Unfortunately, the pay-per-click method of payment for Internet advertising may be subject to fraud and abuse. For example, a competitor of a company that sponsors a pay-per-click advertisement on an Internet web page may have its employees repeatedly click on the advertisement in an effort to drive up its competitor's advertising expenses. Businesses which host Internet advertisements may also have perverse incentives to click on those advertisements in order to generate Internet advertising revenues. In fact, news sources have reported apparent instances where individuals have been hired, often in third world countries where unskilled labor is less expensive, to click on certain Internet advertisements for purposes of generating increased pay-per-click advertising revenues and/or for driving up a competitor's advertising costs. Similar instances have been reported where computer programs that repeatedly click on an Internet advertisement automatically have been used for the same purposes. The potential for these and other types of “click fraud” degrade from the desirability of pay-per-click Internet advertising.